Apparatus for sealing a vacuum chamber

ABSTRACT

An apparatus for sealing a vacuum chamber mainly comprises a plurality of long cylinders for linearly moving first piston rods. The first piston rods connect with a frame elevator. The frame elevator has a second piston rod and guide stems parallel to the first piston rods. While the second piston rod moves parallel to the guide stems by means of the short stroke cylinder, a lever, a transmitting rod and a connecting rod are driven synchronously. The transmitting rod is pivoted with the middle of connecting rod. The direction-changing mechanisms are pivoted at the two ends of the connecting rods for horizontally moving a door to seal the vacuum chamber. The moving direction of the door pushed by direction-changing mechanisms is perpendicular to the moving direction of the second piston rods so that the apparatus has a super thin configuration.

FIELD OF THE INVENTION

[0001] The present invention generally relates to a vacuum processapparatus, such as the vacuum process apparatus for coating thin filmson photoelectric or semiconductor devices, and more particularly to anapparatus for sealing a vacuum chamber.

BACKGROUND OF THE INVENTION

[0002] Vacuum process apparatus have been commonly used in many kinds ofindustries, applied to vacuum thin film coating process of workpiecessuch as liquid crystal substrates or semiconductor wafers. An operatingenvironment inside the vacuum chamber must be maintained close to vacuumpressure. However, due to the different air pressures between the insideand the outside of vacuum chamber, the atmosphere is easy to leak intovacuum chamber through the entrance of workpiece.

[0003] An apparatus for sealing a vacuum chamber is disclosed in U.S.Pat. No. 6,120,611 “apparatus and method for hermetically sealing achamber”. It comprises a ball bearing and a photosensing element forreducing frictional force during hermetically sealing the chamber. It isa sealing apparatus installed at a cylindrical flange of the vacuumchamber for sealing the chamber hermetically, and the door is integratedwith wafer loader so that the apparatus is uneasy to be used orinstalled individually.

SUMMARY

[0004] The main object of the present invention is to provide anapparatus for sealing a vacuum chamber. By means of levers, transmittingrods and connecting rods, a second piston rod pushed forward by a shortstroke cylinder on the frame elevator drives a plurality ofdirection-changing mechanisms to horizontally move a door for sealing avacuum chamber, so that the door of large area or with high weight maybe driven efficiently.

[0005] The secondary object of the present invention is to provide anapparatus for sealing a vacuum chamber. Because of parallel arrangementof the first piston rods for vertically elevating the door, the secondpiston rod for horizontally pushing the door and guide stems, the shellbody can be designed as flat type. Therefore, according to the presentinvention, the apparatus for sealing a vacuum chamber has a super thinconfiguration, so that the moving space of robot arm is not interferedby the chamber door.

[0006] In accordance with the apparatus for sealing a vacuum chamber ofthe present invention, it comprises a plurality of long strokecylinders, a frame elevator and a door. The frame elevator is combinedwith a plurality of first piston rods, at least a second piston rod andat least a guide stem. The long stroke cylinders linearly move the firstpiston rods and the frame elevator. The frame elevator is combined withat least a short stroke cylinder connecting with the second piston rodso the second piston rod moves along a parallel direction of guidestems. The second piston rod is connected to middle of a connecting rodthrough a lever and a transmitting rod. A plurality ofdirection-changing mechanisms are pivoted at the two ends of theconnecting rod. It is preferable that the guide stem is fixedly combinedwith a support frame inside the shell body. The support fame has aplurality of narrow openings for limiting the movement of thedirection-changing mechanisms so that a plurality of direction-changingmechanisms pivoted on the door horizontally push the door to seal thevacuum chamber under the vertical movement of the second piston rod.

DESCRIPTION OF THE DRAWINGS

[0007]FIG. 1 is a perspective view of an apparatus for sealing a vacuumchamber in accordance with an embodiment of the present invention.

[0008]FIG. 2 is a front perspective view showing the apparatus forsealing a vacuum chamber on opening state in accordance with theembodiment of the present invention.

[0009]FIG. 3 is a cross-sectional view along line 3-3 in FIG. 2.

[0010]FIG. 4 is a front perspective view showing the apparatus forsealing a vacuum chamber after moving at the predetermined location inaccordance with the embodiment of the present invention.

[0011]FIG. 5 is a cross-sectional view along line 5-5 in FIG. 4.

[0012]FIG. 6 is a front perspective view showing the apparatus forsealing a vacuum chamber under sealing state in accordance with theembodiment of the present invention.

[0013]FIG. 7 is a cross-sectional view along line 7-7 in FIG. 6.

[0014]FIG. 8 is a front perspective view showing an apparatus forsealing a vacuum chamber in accordance with another embodiment of thepresent invention.

DETAILED DESCRIPTION OF THE PRESENT INVENTION

[0015] Referring to the drawings attached, the present invention will bedescribed by means of the embodiments below.

[0016] An apparatus for sealing a vacuum chamber of the presentinvention is applied to treatment process, which is mounted on vacuumthin film coating treat equipments of workpieces such as semiconductorwafers, liquid crystal substrates, or photoelectric semiconductordevices.

[0017] As shown in FIG. 1 and FIG. 2, an apparatus 100 for sealing avacuum chamber comprises an elevating mechanism, a sealing mechanism, adoor 140 and a shell body 150 for mounting on a vacuum chamber wall 10of a vacuum chamber. The elevating mechanism is configured forvertically moving the door 140 up and down, which comprises a pluralityof long stroke cylinders 110 and first piston rods 111. In thisembodiment there are two sets of long stroke cylinders 110. One end ofeach first piton rod 111 movably connects with the corresponding longstroke cylinder 110 and the other end of the first piston rod 111 isfixedly connected with the frame elevator 130 of the sealing mechanismfor vertically moving the frame elevator 130 to a predetermined point,also the door 140 connects with the frame elevator 130 bydirection-changing mechanisms 160 for moving up or down synchronously.The long stroke cylinders 110 make the first piston rods 111 linearlymove to a predetermined location so the frame elevator 130 may movebetween two locations along a linear direction (as shown in FIG. 2 andFIG. 4).

[0018] The door 140 is installed inside the shell body 150 with propershape such as rectangle, square or circle. In this embodiment the door140 is in square configuration. The flat type shell body 150 has anopening 151 corresponding to the door 140. A guide plate 152 is fixed atone side of the shell 150, which has through holes for the guide stems131 and the second piston rods 121 of the sealing mechanism moving inand passing through the shell body 150.

[0019] The sealing mechanism is configured for horizontally moving thedoor 140 to seal a vacuum chamber, which comprises a frame elevator 130and a support frame 132. Two guide stems 131 are fixedly equipped at theinner side of the frame elevator 130 with one ends and pass through theguide plate 152 of shell 150, then guide stems 131 are mounted on thesupport frame 132 inside the shell 150 with the other ends. A pluralityof narrow openings 133 are formed on the support frame 132 to providemoving spaces of pivoting axes at first ends 162 a of sliding blocks 162of direction-changing mechanisms 160 (as shown in FIG. 3). The supportframe 132 has a fixed across bar 134 with supporting axes 136 forpivoting the levers 123. Besides, the O-rings 135 are fitted around thethrough holes of guide plate 152 where guide stems 131 and second pistonrods 121 pass through in order to enhance air-tight and cushioningeffect of mechanical movement.

[0020] Furthermore, at least a short stroke cylinder 120 is fitted onthe frame elevator 130 for moving at least a second piston rod 121 to apredetermined location. In this embodiment two short stroke cylinders120 are fitted on the frame elevator 130 to join two second piston rods121. When the short stroke cylinders 120 push the second piston rods121, the second piston rods 121 move parallel to the guide stems 131 (asshown in FIG. 4 and FIG. 6). Also, the first piston rods 111, the secondpiston rods 121 and the guide stems 131 are mutually parallel so theapparatus for sealing a vacuum chamber is flat shape.

[0021] As shown in FIG. 2 and FIG. 3, the second piston rods 121 passingthrough the guide plate 152 of shell 150 connect with one ends of thelevers 123. The levers 123 connect with fixed across bar 134 of supportframe 132 by supporting axes 136. The other ends of the levers 123 arepivoted with the transmitting rods 124. It is better that eachsupporting axis 136 is close to the corresponding transmitting rods 124so the levers 123 have a transmission effect of leverage. Also, one endof transmitting rod 124 is pivoted to the middle of the connecting rod122. The two ends of connecting rods 122 are pivoted with at least adirection-changing mechanism 160 respectively. The door 140 is movedhorizontally by means of the direction-changing mechanisms 160 forsealing the opening 151 of shell 150.

[0022] As shown in FIG. 3 and FIG. 7, each direction-changing mechanism160 includes a sliding block 162, a support block 163 and a mountingblock 161. The mounting block 161 is fixedly fitted on the door 140. Thesecond end 162 c of the sliding block 162 is pivoted with the mountingblock 161. And the first end 162 a of the sliding block 162 is pivotedwith the connecting rod 122. The moving space of pivot axis at first end162 a of the sliding block 162 is limited by narrow opening 133 of thesupport frame 132. Also, one end of the support block 163 is pivoted atthe middle point 162 b of the sliding block 162 and the other end 163 aof the support block 163 is pivoted with the support frame 132.

[0023] As shown in FIG. 2 and FIG. 3, when the apparatus 100 for sealingthe vacuum chamber mentioned above is on start state, the long strokecylinders 110 linearly stretch out the first piston rods 111, so thatthe frame elevator 130 moves to a direction in which is far away fromlong stroke cylinder 110 and at the same time the door 140 also goesaway from the opening 151 of shell 150 to open the chamber. As shown inFIG. 3, a larger interval is kept between the first end 162 a of slidingblock 162 and the end 163 a of the support block 163 during verticalmoving process, so there is a gap between the door 140 and the sealingsurface of opening 151 of shell 150 for moving the door 140 withoutfriction caused by contacting the shell 150.

[0024] When the vacuum chamber is going to be sealed, the elevatingmechanism is in action. As shown in FIG. 4 and FIG. 5, the long strokecylinders 110 linearly withdraw the first piston rods 111 from apredetermined point, then, the frame elevator 130 moves to the directionclose to the long stroke cylinders 110 and simultaneously the door 140moves close to the opening 151. Meantime, as shown in FIG. 5, the shortstroke cylinders 120 are out of action so the gap between the first end162 a of sliding block 162 and the end 163 a of support block 163 ismaintained. Due to the unsealed gap between the door 140 and the opening151 of shell 150, the door 140 can smoothly be vertically moved to thepredetermined position without contacting the shell 150 beforehorizontally sealing the opening 151.

[0025] Thereafter in order to seal the opening 151 of shell 150completely, the apparatus 100 starts to drive the sealing mechanismafter the first piston rods 111 move to a predetermined point. As shownin FIG. 6 and FIG. 7, the second piston rod 121 is connected with oneend of a lever 123. The supporting axis 136 of the lever 123 is pivotedto the fixed across bar 134 of support frame 132. The other end of thelever 123 is pivoted with a transmitting rod 124 and further thetransmitting rod 124 is connected with middle of a connecting rod 122.While the second piston rods 121 are driven by the short strokecylinders 120, the levers 123 is rotated at supporting axes 136 andsynchronously drive the transmitting rods 124 and the connecting rods122. The direction-changing mechanisms 160 on two ends of the connectingrods 122 also are driven, so that the first ends 162 a of sliding blocks162 of direction-changing mechanisms 160 move close to the ends 163 a ofsupport blocks 163. According to Cardan circle direction-changingtheory, while there is a variation of interval between the first end 162a of sliding block 162 and the end 163 a of support block 163 (becomesmaller), the second ends 162 c of sliding blocks 162 ofdirection-changing mechanisms 160 will horizontally move. Therefore, themounting blocks 161 are pushed linearly and the door 140 synchronouslycontacts the sealing surface of opening 151 of shell 150 for sealing theopening 151 of shell 150. The moving direction of the door 140 pushed bydirection-changing mechanisms 160 is perpendicular to the movingdirection of the second piston rods 121 to completely seal the opening151 of shell 150. It is preferable that an elastic ring cushion 141 isfitted at the perimeter of compression surface of the door 140 forincreasing the air-tight effect of the door 140.

[0026] According to the present invention, the apparatus 100 for sealinga vacuum chamber can synchronously drive the multiple direction-changingmechanisms 160 evenly connecting to the door 140 by means of levers 123,transmitting rods 124 and connecting rods 122. Therefore, the vacuumchamber can be sealed reliably and economically by a door with largearea or big weight. Also, the guide stems 131 of sealing mechanism aredisposed parallel to the second piston rods 121 and the first pistonrods 111, and those are even disposed on a same plane so that the shell150 can be designed as a flat type. Therefore, the apparatus 100 forsealing a vacuum chamber of the present invention has a super thinconfiguration and the moving space of robot arm is not interfered whileopening or sealing a chamber door.

[0027] In the second embodiment of the present invention illustrated inFIG. 8, an apparatus 200 for sealing a vacuum chamber includes aplurality of direction-changing mechanisms 260 synchronously driven by asecond piston rod 221 only, it comprises long stroke cylinders 220,first piston rods 211, direction-changing mechanisms 260, connectingrods 222, levers 223, transmitting rods 224, guide stems 231, door 240,shell 250 and so on are the same as the first embodiment. The apparatus200 further comprises a frame elevator 230 that fixedly fits a pluralityof the first piston rods 211, parellel guide stems 231 and a shortstroke cylinder 220. The other end of the first piston rods 211 areenclosed by the corresponding long stroke cylinders 210 for moving theframe elevator 230 to a predetermined point. The guide stems 231 arefixedly connected with a support frame 232 passing through the guideplate 252 of shell 250. The support frame 232 has narrow openings (notshown in drawings) for limiting the direction-changing mechanisms 260.It is better that a plurality of O-rings 235 are formed on the guideplate 252 around the guide stems 231 and the second piston rod 221 forincreasing air-tight effect. The short stroke cylinder 220 encloses oneend of the second piston rod 221 that is parallel to and located betweenthe first piston rods 211 and the guide stems 231 so that the secondpiston rod 221 may move to a predetermined point along a paralleldirection of the guide stems 231. Also the second piston rod 221 isconnected to the middle of a push rod 225. And the two ends of the pushrod 225 are pivoted with two second transmitting rods 226 respectively.Each second transmitting rod 226 is pivoted with the corresponding oneend of the lever 223 and the levers 223 are pivoted on the fixed acrossbars 234 of support frames 232 by support axes 236. The other end ofeach lever 223 is pivoted with a transmitting rod 224 and thetransmitting rod 224 is pivoted with the middle of a connecting rod 222.The two ends of each connecting rod 222 are pivoted with a plurality ofdirection-changing mechanisms 260 respectively, such as mounting blocks261, sliding blocks 262 and support blocks 263, etc. When the secondpiston rod 221 extends from the short stroke cylinder 220, theconnecting of push rods 225, the second transmitting rods 226, levers223, transmitting rods 224 and connecting rods 222, thedirection-changing mechanisms 260 synchronously are driven to push thedoor 240 for evenly sealing the opening 251 of shell 250.

[0028] The above description of embodiments of this invention isintended to be illustrative and not limiting. Other embodiments of thisinvention will be obvious to those skilled in the art in view of theabove disclosure.

What is claimed is:
 1. An apparatus for sealing a vacuum chambercomprising: a plurality of long stroke cylinders with a plurality offirst piston rods for moving a frame elevator; a frame elevator mountingthe first piston rods, guide stems and at least a short stroke cylinder,wherein another end of each first piston rod is enclosed by the longstroke cylinders for linearly moving the frame elevator along a fixeddirection, there is a support frame connected at the other ends of theguide stems, each short stroke cylinder enclosed one end of a secondpiston rod, the second piston rod is parallel to the guide stems and thefirst piston rods for moving along a parallel direction of the guidestems, each second piston rod connects through at least a lever, atleast a transmitting rod and a connecting rod connected, the lever has asupport axis close to the transmitting rod, the support axis is pivotedon the support frame, one end of each lever is pivoted with the secondpiston rod and the other end of the lever is pivoted with thetransmitting rod, each transmitting rod is pivoted with the middle ofthe connecting rod, the two ends of each connecting rods pivoted with atleast a direction-changing mechanism respectively; and a door pivotingwith the direction-changing mechanisms; when the long stroke cylindersmoving the frame elevator to the predetermined position, the shortstroke cylinder through the second piston rods, transmitting rods,levers and connecting rods moves the direction-changing mechanisms tomake the door linearly move to the vacuum chamber for sealing the vacuumchamber.
 2. An apparatus for sealing a vacuum chamber in accordance withclaim 1, wherein each direction-changing mechanism comprises a slidingblock, a support block and a mounting block, the mounting blocks aremounted on the door, the first ends of the sliding blocks are pivotedwith the connecting rods by pivot axes, each pivot axis of the slidingblock moves in the corresponding narrow opening on the support frame,the second ends of the sliding blocks are pivoted with the mountingblocks mounted on the door, the middles of the slide blocks are pivotedwith the support blocks, and the other ends of the support blocks arepivoted with the support frame.
 3. An apparatus for sealing a vacuumchamber in accordance with claim 1, wherein the support frame includes afixed across bar for pivoting with the support axis of the lever.
 4. Anapparatus for sealing a vacuum chamber in accordance with claim 1,further comprising a ring cushion on the door.
 5. An apparatus forsealing a vacuum chamber in accordance with claim 1, further comprisinga push rod and two second transmitting rods pivoted with the two ends ofthe push rod between the second piston rod and the levers, wherein themiddle of the push rod is pivoted with the second piston rod, and thesecond transmitting rods are pivoted with the ends of the levers.
 6. Anapparatus for sealing a vacuum chamber comprising: a flat shell havingan opening; a door fitted in the shell, the door mounting a plurality ofdirection-changing mechanisms; a sealing mechanism including a frameelevator, a support frame and guide stems for fixedly connecting withthe frame elevator and the support frame, wherein at least a shortstroke cylinder having a second piston rod is fitted on the frameelevator for moving the second piston rod to the predetermined point,the second piston rod drives at least a lever, a transmitting rod and aconnecting rod, the support axis of the lever is pivoted on the supportframe, the transmitting rod connects with the lever and the middle ofthe connecting rod, the two ends of the connecting rod are pivoted withthe direction-changing mechanisms respectively for moving the door tothe opening of the shell; and an elevating mechanism including aplurality of long stroke cylinders with first piston rods, wherein thefirst piston rods connect the frame elevator, the long stroke cylindersdrive the first piston rods to the predetermined points for verticallymoving the door and the sealing mechanism, and the first piston rods areparallel to the second piston rod.
 7. An apparatus for sealing a vacuumchamber in accordance with claim 6, wherein the shell has a guide platefor passing through the guide stems and the second piston rod.
 8. Anapparatus for sealing a vacuum chamber in accordance with claim 6,wherein each direction-changing mechanism includes a sliding block, asupport block and a mounting block, wherein the mounting block ismounted on the door, the first end of the sliding block is pivoted withthe connecting rod, the second end of the sliding block is pivoted withthe mounting block, the middle of the slide block is pivoted with thesupport block, and the other end of the support block is pivoted withthe support frame.
 9. An apparatus for sealing a vacuum chamber inaccordance with claim 8, wherein the support frame has a plurality ofnarrow openings for offering the moving spaces of pivot axes at thefirst ends of the sliding blocks.
 10. An apparatus for sealing a vacuumchamber in accordance with claim 6, wherein the support frame includes afixed across bar for pivoting the lever.
 11. An apparatus for sealing avacuum chamber in accordance with claim 6, wherein a ring cushion isfitted on the door.
 12. An apparatus for sealing a vacuum chamber inaccordance with claim 6, further comprising a push rod and two secondtransmitting rods pivoting the two ends of the push rod between thesecond piston rod and the levers, wherein the middle of the push rod ispivoted with the second piston rod and the second transmitting rods arepivoted with the ends of the levers.